This invention concerns forming a creeling tail on one end of a package core in connection with winding a strand on the core to form a strand package. More particularly, the invention concerns a method and apparatus for forming the creeling tail at the large end of a conical package core.
In winding a strand upon a conical package core, the core is typically supported at its ends for rotation about its axis. The core is rotationally driven through frictional contact with a rotating drive roll, a traversing strand guide being provided to move the strand back and forth along the rotating core so as to produce a helically wound strand package on the core. The core is generally oriented such that a generatrix on the conical surface having a portion in contact with the drive roll is parallel to the axis of the drive roll. While the surface of the drive roll may be uniformly cylindrical, it is preferable to provide the drive roll with a medial portion having an annular surface of larger diameter than the remainder of the drive roll so that the cone is effectively driven by frictional engagement only at a medial portion of the core. It is thus apparent that the large end of the conical core rotates with a higher peripheral speed than the small end thus resulting in greater tension on the strand when it is being wound on the large end of the core. In order to reduce the effect of the winding rate being variable over the length of the core, various types of strand accumulators have been employed to store some of the strand when the winding rate is low at the small end of the core and to release the stored strand when the winding rate is high at the larger end of the core, thus maintaining the tension on the strand substantially uniform during winding. Such strand accumulators may operate satisfactorily when the strand is being wound during the normal winding operation, but they are not able to store enough strand to accommodate forming the creeling tail at the large end of the core since several windings must be made in one place. Thus, the tension on the strand during winding of the creeling tail is so great that strand breakage is a significant problem. This is particularly true when the feed rate from the yarn source is essentially fixed, as, for example, in an open end spinning machine.
In Richard A. Schewe's U.S. Pat. No. 4,138,071 a dual drive for cone winding is disclosed in which the package core is initially effective near the large end of the conical core so that the peripheral speed at the large end of the core during winding of the creeling tail is within normal winding parameters so that high tension problems are substantially eliminated. While this invention works well with conical cores of relatively large diameter, it has been found that when using conical cores having the same length and cone angle but being of smaller diameter, the ratio of the radii at the medial portion and the large end portion is not as great and the drive located near the large end of the core is not sufficiently positive or effective to give good results in all cases.
Regarding another aspect of forming creeling tails, the strand is initially held in position near the large end of the core during forming of the creeling tail by means of a fixed guide located proximate the large end of the core. Heretofore it has been necessary to manually move the strand out of the fixed guide so that it may be picked up by the traversing guide after the creeling tail has been formed. In certain applications, such as in an open end spinning machine having an automation feature for piecing up operations, it is desirable to provide for automatic release and transfer of the strand from the fixed guide to the traversing guide subsequent to forming of the creeling tail.
Thus, there has been a need for a creeling-tail-forming apparatus which provides positive drive at the large end of the conical core in all cases as well as providing for automatic transfer of the strand from the fixed guide to the traversing guide.